We are replacing a neo-angle shower enclosure in our upstairs bathroom. The original one installed 7 years ago has failed (cheap fibreglass Home Depot version) and we are replacing the pan with an Acrylic model. For the surround, we are planning a glass mosaic tile which requires a modified latex thinset.

I would prefer to use Desshield over Hardibacker...but have read on the net that the latex thinset will not bond to the acrylic membrane on the Densshield. Does anyone have any experience with this, or suggestions?

For what it's worth, I just set thousands of glass mosaics on Hardibacker using MegaFlex and MegaLite. No problems. Dampen the Hardibacker with a sponge as instructed before you trowel on your thinset.

I've never used the Denshield, so I can't comment one way or the other on it.

I've only personally used dense-shield once a long time ago, But I've sat through one of their panel discussions and listened to another seminar on the product and was impressed with the knowledge of the company. If my memory serves me they have no problem with modified thinsets bonding to the board...In fact I'm certain that would be their recomendation. May check with your Glass manf. to see what they would like you to use. Some Glass companies have very specific bonding needs/brand preferences.

Do review the instructions for Dense-sheild if you go that route..They want seams and corners treated in a specific fashion for waterproofing.

We'll be here if you have more questions so feel free to ask away....Good luck and have fun.

Treating the edges of the Denssheild like Trask said is absolutely critical to this job lasting a long time. Many people have installed the material w/o treating the seams, and have regretted it. Do a search here on this site and you'll see tons of discussion on using the stuff.

In this case, I personally would choose Durock first, and Hardi second. It's my personal preference.

Calling the tile manufacturer for specific mortar requirements (and any others) is an excellent idea. Glass tiles are not all made the same and vary in their requirements.

if I recall correctly it's not just the seams with Denshield - it's also any penetration of the skin that has to be waterproofed. that means every place you drive a nail or screw to attach it to studs. and any plumbing penetrations. and the advantage of Denshield over Hardi is....?

oh, that's right - it's easier to cut.

at least that's what I think I recall from my own research back when I considered using it and before I settled on Kerdi over drywall.

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Now you're throwing me for a loop! Over what application would Kerdi be employed?

The new pan leaves about a three quarter inch gap between the ceramic floor and the pan on the outside edge of the neo-angle (in other words, the two sides fit nice, but the portion under the door is where the gap is)....is it possible to fill the gap with a filler of some kind, then use a fibreglass composite shoe moulding around the new acrylic base (properlly caulked, of course)? I DO NOT want to get involved with retiling the floor at this point...

Our new neo-angle acrylic shower pan is not exactly the same dimensions as the piece of crap fibreglass one we just had to repace. I have not installed the new pan yet, but in a dry run I discovered when the pan is flush with the studs, the two sides of the angled portion fit the profile of the old pan, but it leaves about a three quarter inch gap on the longer side right under the door.

I was thinking I could fill this gap with a marine exopy/bondo type material, then buy a waterproof fiberglass shoe moulding to trim out the shower pan. After properly caulking, shouldn't this address the problem? Please don't tell me I have to replace the tiles....

The gap is approximately 3/4 of an inch... The curb of the pan is hollow. I am having my plumber install it after he fixes a drain issue we have been having...so not sure if I need to address this problem before or after he installs the pan next week.

I see you have two threads going on, so I've merged them. Let's keep your questions all together for this project to avoid duplication of effort and confusion. Plus the history of what led up to the latest question oftentimes changes the answers given out.

Ok, well, if you have that large of a gap and you think the quarter round molding you mentioned looks aesthetically pleasing, go for it. Make sure the plumber supports the underside of the pan per manufacturer's directions. Oftentimes it means a thin bed of mortar to support it.

Thanks for merging the threads Bubba - still getting used to the site but I love it thus far.

Yes, I can get a hold of some pretty nice shoe moulding that will do the job. I will point out the issue to the plumber and make sure he adds the necessary support as needed.

I am still a little warry regarding which backer board to use...so if anyone has more thoughts keep them coming. I was pretty surprised that there wasn't more water damage when I took the old surround and greeboard down, as the fibreglass had developed a few cracks and the old pan was not properly supported...causing gaps around the base of the shower surround. That issue is what got this project going...and since our one wall is only 65" from the top of the acrylic base to the ceiling we decided to tile. Most fibreglass surrounds come in stock 70" lengths...but the tile is a much better look anyhow.

Additionally, I am having a very well respected shower door contractor measure and install the door enclosure. the new tile will run about 1-2" outside of the enclosure...any suggestions on how to finish the edge of glass mosaics?

I know I have alot out there in this thread but I really appreciate the advice thus far. Thanks!!!!

Hey Kyle,
I used to use hardi quite often,and still do for certain applications, but in the last year have switched to denshield for shower walls. The acrylic coating on it that acts as a vapor barrier is very durable and makes a lot of sense to me. Why allow water to travel all the way through your tile substrate? Why not stop it directly behind the tile and it's mudbed? It also eliminates the step of installing a vapor barrier behind the substrate. As far as sealing fastener/plumbing penetrations, it's as easy as it gets (who likes to mud and tape inside corners?). Use a 100% silicone caulk, and get a neutral cure so you don't have to smell it as you use it. I use white so that when it's applied I can see that all spots are done properly. For the fastener spots, I just dab the caulk on my finger and apply it to the spots. I tool it around a bit to ensure adhesion. If your denshield is dusty prior to this step just dampen a sponge, wipe down, towel or let air dry, and then apply caulk. Doing this only takes about 10 minutes for a 30" x 60" shower.

One other benefit and an example of where "less is more" is that you can use a dry set mortar if you like and save a few more dollars, yet still get a superior product. The denshield doesn't suck the moisture from the t-set, allowing it to cure out the way it should. As far as the cutting of it goes, score and snap straight cuts, for plumbing holes I use a hole saw for pipes and a regular drywall saw (keyhole saw) for the valves. Super simple.